Update ruff configuration to use modern lint section format

Author: TexasCoding

pyproject.toml

@@ -103,21 +103,6 @@ include = ["/src", "/tests", "/docs", "README.md", "CHANGELOG.md", "LICENSE"]
 line-length = 88
 target-version = "py312"
 src = ["src", "tests"]
-select = [
-    "E",   # pycodestyle errors
-    "W",   # pycodestyle warnings  
-    "F",   # Pyflakes
-    "I",   # isort
-    "B",   # flake8-bugbear
-    "C4",  # flake8-comprehensions
-    "N",   # pep8-naming
-    "UP",  # pyupgrade
-    "RUF", # Ruff-specific rules
-    "SIM", # flake8-simplify
-    "TID", # flake8-tidy-imports
-    "PIE", # flake8-pie
-    "PT",  # flake8-pytest-style
-]
 exclude = [
     ".bzr",
     ".direnv",
@@ -147,6 +132,23 @@ exclude = [
     "venv",
 ]
 
+[tool.ruff.lint]
+select = [
+    "E",   # pycodestyle errors
+    "W",   # pycodestyle warnings  
+    "F",   # Pyflakes
+    "I",   # isort
+    "B",   # flake8-bugbear
+    "C4",  # flake8-comprehensions
+    "N",   # pep8-naming
+    "UP",  # pyupgrade
+    "RUF", # Ruff-specific rules
+    "SIM", # flake8-simplify
+    "TID", # flake8-tidy-imports
+    "PIE", # flake8-pie
+    "PT",  # flake8-pytest-style
+]
+
 ignore = [
     "E501",  # Line too long (handled by formatter)
     "B008",  # Do not perform function calls in argument defaults
@@ -161,12 +163,12 @@ unfixable = []
 # Allow unused variables when underscore-prefixed
 dummy-variable-rgx = "^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$"
 
-[tool.ruff.per-file-ignores]
+[tool.ruff.lint.per-file-ignores]
 "src/project_x_py/indicators/__init__.py" = ["N802"]  # Allow uppercase function names for TA-Lib style compatibility
 "tests/**/*" = ["S101", "PLR2004", "PLR0913", "PLR0915"]
 "__init__.py" = ["F401"]
 
-[tool.ruff.isort]
+[tool.ruff.lint.isort]
 known-first-party = ["project_x_py"]
 force-single-line = false
 combine-as-imports = true